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/*
This file is part of GNUnet.
(C) 2010 Christian Grothoff
GNUnet is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published
by the Free Software Foundation; either version 3, or (at your
option) any later version.
GNUnet is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
General Public License for more details.
You should have received a copy of the GNU General Public License
along with GNUnet; see the file COPYING. If not, write to the
Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA.
*/
/**
* @file vpn/gnunet-daemon-vpn.c
* @brief
* @author Philipp Tölke
*/
#include <platform.h>
#include "gnunet-vpn-tun.h"
#include "gnunet_common.h"
#include "gnunet_protocols.h"
#include "gnunet-vpn-helper-p.h"
#ifndef _LINUX_IN6_H
// This is in linux/include/net/ipv6.h.
#define MAX_SIZE (65535 - sizeof(struct GNUNET_MessageHeader))
struct in6_ifreq {
struct in6_addr ifr6_addr;
uint32_t ifr6_prefixlen;
unsigned int ifr6_ifindex;
};
#endif
int running = 1;
void term(int sig) {
fprintf(stderr, "Got SIGTERM...\n");
if (sig == SIGTERM)
running = 0;
}
static void set_address6(char* dev, char* address, unsigned long prefix_len) { /* {{{ */
int fd = socket(AF_INET6, SOCK_DGRAM, 0);
struct ifreq ifr;
struct in6_ifreq ifr6;
struct sockaddr_in6 sa6;
memset(&sa6, 0, sizeof(struct sockaddr_in6));
sa6.sin6_family = AF_INET6;
/* FIXME */ inet_pton(AF_INET6, address, sa6.sin6_addr.s6_addr);
memcpy((char *) &ifr6.ifr6_addr, (char *) &sa6.sin6_addr, sizeof(struct in6_addr));
strncpy(ifr.ifr_name, dev, IFNAMSIZ);
if (ioctl(fd, SIOGIFINDEX, &ifr) < 0) {
perror("SIOGIFINDEX");
}
ifr6.ifr6_ifindex = ifr.ifr_ifindex;
ifr6.ifr6_prefixlen = prefix_len;
if (ioctl(fd, SIOCSIFADDR, &ifr6) < 0) {
perror("SIOCSIFADDR");
}
/* FIXME */ ioctl(fd, SIOCGIFFLAGS, &ifr);
ifr.ifr_flags |= IFF_UP | IFF_RUNNING;
/* FIXME */ ioctl(fd, SIOCSIFFLAGS, &ifr);
close(fd);
} /* }}} */
static void set_address4(char* dev, char* address, char* mask) { /* {{{ */
int fd=0;
struct sockaddr_in* addr;
struct ifreq ifr;
memset(&ifr, 0, sizeof(struct ifreq));
addr = (struct sockaddr_in *)&(ifr.ifr_addr);
memset(addr, 0, sizeof(struct sockaddr_in));
addr->sin_family = AF_INET;
addr->sin_addr.s_addr = inet_addr(address);
/* FIXME */ inet_pton(AF_INET, address, &addr->sin_addr.s_addr);
fd = socket(PF_INET, SOCK_DGRAM, 0);
if(fd < 0) {
perror("socket()");
return;
}
strncpy(ifr.ifr_name, dev, IFNAMSIZ);
if(ioctl(fd, SIOCSIFADDR, &ifr) != 0 ) {
perror("SIOCSIFADDR");
close(fd);
return;
}
addr = (struct sockaddr_in*)&(ifr.ifr_netmask);
/* FIXME */ inet_pton(AF_INET, mask, &addr->sin_addr.s_addr);
if(ioctl(fd, SIOCSIFNETMASK, &ifr) != 0 ) {
perror("SIOCSIFNETMASK");
close(fd);
return;
}
/* FIXME */ ioctl(fd, SIOCGIFFLAGS, &ifr);
ifr.ifr_flags |= IFF_UP | IFF_RUNNING;
/* FIXME */ ioctl(fd, SIOCSIFFLAGS, &ifr);
close(fd);
} /* }}} */
void setnonblocking(int fd) {/*{{{*/
int opts;
opts = fcntl(fd,F_GETFL);
if (opts < 0) {
perror("fcntl(F_GETFL)");
}
opts = (opts | O_NONBLOCK);
if (fcntl(fd,F_SETFL,opts) < 0) {
perror("fcntl(F_SETFL)");
}
return;
}/*}}}*/
int main(int argc, char** argv) {
unsigned char buf[MAX_SIZE];
char dev[IFNAMSIZ];
memset(dev, 0, IFNAMSIZ);
signal(SIGTERM, &term);
int fd_tun = init_tun(dev);
if (fd_tun < 0) {
fprintf(stderr, "Could not initialize tun-interface: %s\n", strerror(errno));
exit(1);
}
{
// TODO: get this out of argv
char address[] = "1234::1";
unsigned long prefix_len = 16;
set_address6(dev, address, prefix_len);
}
{
char address[] = "10.10.10.1";
char mask[] = "255.255.255.252";
set_address4(dev, address, mask);
}
uid_t uid = getuid ();
if (setresuid (uid, uid, uid) != 0 )
fprintf (stderr, "Failed to setresuid: %s\n", strerror(errno));
setnonblocking(0);
setnonblocking(1);
setnonblocking(fd_tun);
fd_set fds_w;
fd_set fds_r;
int rea = 1;
int wri = 1;
int write_fd_possible = 0;
int write_stdout_possible = 0;
outer:
while((rea == 1 || wri == 1) && running == 1) {
FD_ZERO(&fds_w);
FD_ZERO(&fds_r);
if (rea) {
FD_SET(fd_tun, &fds_r);
if (!write_stdout_possible)
FD_SET(1, &fds_w);
}
if (wri) {
FD_SET(0, &fds_r);
if (!write_fd_possible)
FD_SET(fd_tun, &fds_w);
}
int r = select(fd_tun+1, &fds_r, &fds_w, (fd_set*)0, 0);
if(r > 0) {
if (FD_ISSET(fd_tun, &fds_w)) write_fd_possible = 1;
if (FD_ISSET(1, &fds_w)) write_stdout_possible = 1;
if (FD_ISSET(0, &fds_r) && write_fd_possible) {
write_fd_possible = 0;
struct suid_packet *pkt = (struct suid_packet*) buf;
r = read(0, buf, sizeof(struct GNUNET_MessageHeader));
if (r <= 0) {
fprintf(stderr, "read-error: %m\n");
shutdown(fd_tun, SHUT_WR);
shutdown(0, SHUT_RD);
wri=0;
goto outer;
}
if(pkt->hdr.type != ntohs(GNUNET_MESSAGE_TYPE_VPN_HELPER)) abort();
while (r < ntohs(pkt->hdr.size)) {
int t = read(0, buf + r, ntohs(pkt->hdr.size) - r);
if (r < 0) {
fprintf(stderr, "read-error: %m\n");
shutdown(fd_tun, SHUT_WR);
shutdown(0, SHUT_RD);
wri=0;
goto outer;
}
r += t;
}
r = 0;
while (r < ntohs(pkt->hdr.size) - sizeof(struct GNUNET_MessageHeader)) {
int t = write(fd_tun, pkt->data, ntohs(pkt->hdr.size) - sizeof(struct GNUNET_MessageHeader) - r);
if (t < 0) {
fprintf(stderr, "write-error 3: %m\n");
shutdown(fd_tun, SHUT_WR);
shutdown(0, SHUT_RD);
wri = 0;
goto outer;
}
r += t;
}
} else if (write_stdout_possible && FD_ISSET(fd_tun, &fds_r)) {
write_stdout_possible = 0;
r = read(fd_tun, buf, MAX_SIZE);
if (r <= 0) {
fprintf(stderr, "read-error: %m\n");
shutdown(fd_tun, SHUT_RD);
shutdown(1, SHUT_WR);
rea = 0;
goto outer;
}
struct GNUNET_MessageHeader hdr = { .size = htons(r + sizeof(struct GNUNET_MessageHeader)), .type = htons(GNUNET_MESSAGE_TYPE_VPN_HELPER) };
r = 0;
while(r < sizeof(struct GNUNET_MessageHeader)) {
int t = write(1, &hdr, sizeof(struct GNUNET_MessageHeader) - r);
if (t < 0) {
fprintf(stderr, "write-error 2: %m\n");
shutdown(fd_tun, SHUT_RD);
shutdown(1, SHUT_WR);
rea = 0;
goto outer;
}
r += t;
}
while(r < ntohs(hdr.size)) {
int t = write(1, buf, ntohs(hdr.size) - r);
if (t < 0) {
fprintf(stderr, "write-error 1: %s, written %d/%d\n", strerror(errno), r, ntohs(hdr.size));
shutdown(fd_tun, SHUT_RD);
shutdown(1, SHUT_WR);
rea = 0;
goto outer;
}
r += t;
}
}
}
}
close(fd_tun);
return 0;
}
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